What a Crash

Science, Sentiment, and 38,368 Guideline Comments

What happens when a careful consideration of science collides with strong sentiment in 38,368 dietary guideline comments? The short answer is public policy. Without a doubt, it’s messy. Simply wading through all those comments is a huge task. A new paper in the American Journal of Clinical Nutrition tries to make sense of them, using natural language processing (NLP).

In sum, the picture that emerges reflects themes that play out every day in debates over nutrition policy: angst about dairy products, added sugars, and health.

Sorting Through Mindless Repetition

Burying policymakers in public comments has become a cottage industry. In 2010, dietary guidelines drew about 2,000 comments from the public. The 2020 guidelines drew almost 20 times more. So Joseph Lindquist and colleagues used NLP to weed out mindless repetition in that huge volume of guideline comments. In this age of social media, people with an agenda have found ways to swarm the public commenting process.

In the end, those 39,368 comments fell to a more manageable number – 1,645. Then from that number the three themes emerged.

Is Dairy Essential?

The first thing to know is that dietary guideline commenters were agitated about dairy products. The top theme that emerged was all about telling the world that dairy products are unnecessary. Though folks clearly have strong sentiments about this, the authors note that some facts might conflict with these feelings:

“It is worth noting that this sentiment runs counter to the need for adequate calcium intake. In fact, some analyses suggest that it is quite difficult or impossible to provide adequate calcium intake while meeting other nutrient recommendations with dairy-free diets.”

In the end, the 2020 dietary guidelines included recommendations for low-fat and fat-free dairy, but vocal advocates for veganism continue to express their opposition to this.

Cutting Added Sugars

Commenters also had a lot to say about added sugars. They were all in for the proposal to cut the limit on added sugar by almost half – from ten percent of total calories to only six percent. Emotions of fear were embedded in these comments: “added sugars are contributing to an obesity crisis among our youngest children.”

In the end, USDA and HHS decided to omit this recommendation from the 2020 dietary guidelines. Nutrition policy advocates were disappointed, but Americans are not even meeting the recommended ten percent limit.

Health and Science

The last group of guideline comments were quite diverse but tied together with aspirations for health. Beyond that theme of aspirations, these comments broke down into three distinct subgroups. One was all about the healthfulness of dairy products – the flip side of the campaign of comments to expunge dairy from the guidelines. The second subgroup extolled the nourishing virtues of beef. “No other food delivers the same nutrient-rich package as a three-ounce serving of beef,” said these commenters.

The final subgroup was wishing simply that the final guidelines would make us all healthy by following the scientific report of the Dietary Guidelines Committee.

In the end, this is the tension that defines the dietary guidelines. Public sentiment about nutrition is strong. It doesn’t always line up with nutrition science. Jeanne Blankenship, a co-author of this paper, summed up the dilemma quite well:

“The challenge is that the numbers and repetition associated with advocacy do not necessarily match with the science. It’s the emotional and consumer perspective. It is important since we want to meet consumers where they are. But no matter how many people think something that doesn’t change scientific facts.”

Click here for the paper in AJCN. For further perspective on the 2020 guidelines from AJCN, click here and here.

What a Crash, illustration by Kazimir Malevich / WikiArt

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June 18, 2021